13.Once upon a time,a hippo lived in a river next to a big tree.A beautiful bird in the tree could not only fly but also sing(1)
,which made the hippo feel sad for himself.For this,the bird said to the hippo, "You are so(2)
to be so big and such a good swimmer." One day,the hippo came out of the river and(3)
the tree.However,when he tried to climb the tree,he found that he didn't have wings(4)
claws to climb with. (5)
that he would never climb up the tree,he(6)
placed his heavy body against the tree until it fell down to the ground.Then,he walked onto the leaves of the fallen tree and began(7)
. Unfortunately,hippos can't sing either.All that came from his mouth were horrible sounds.(8)
the other animals heard this,they all met together to make fun of the hippo. He was so shameful by this that he realized how special he was and how different he was(9)
the bird,so he decided to never feel sorry for(10)